U.S. Pat. No. 5,743,070 (the S P Patent) entitled PACKAGING MACHINE, MATERIAL and METHOD discloses a machine for use in packaging which has been highly successful commercially. The S P Patent and patents which resulted from divisional applications claim a machine and a plastic web used by that machine as well as a process of making packages.
With the machine of the S P Patent the web is fed first through a slitter which splits a top portion into two lips that are respectively grasped between associated pairs of belts for transport through a load section. The belts which transport the web through the load section are more fully described in U.S. Pat. No. 5,722,218 issued Mar. 3, 1998 and entitled Plastic Transport System, herein (the Load Belt Patent).
As the web is fed to the load section, the lips are spread to effect the sequential opening of the side connected bags, each into a rectangular opening for receiving a product to be packaged. The lips are then returned to juxtaposed relationship and trimmed as the lips are grasped by further belts in a sealer section. The further belts are preferably belts of the type described and claimed in U.S. Pat. No. 6,170,238 issued Jan. 9, 2001 and entitled Sealing Machine and Method, herein (the Sealer Belt Patent).
The SP, Load Belt and Sealer Belt Patents are herein incorporated by reference in their entireties.
While the machine of the referenced patents has proved highly successful it is relatively difficult to clean and not suitably constructed for use in packaging food products. Accordingly, it would be desirable to provide a novel and improved machine of the SP Patent constructed to facilitate cleaning and to be adaptable for food packaging.